3pcs 15W 3A Battery Boost Charging Module High Power UPS 18650 Lithium Battery Boost Charging and Discharging UPS Uninterruptible Power Supply (9V)

Equipped with dual-color LED to show the charging status, the green light stays on when fully charged, and charging halts automatically. The module features two 18650 battery holders, a universal Micro USB charging port, and direct DC5V input for charging the lithium battery.
Boost circuit: peak power up to 20W, rated power up to 15W, BOST boost circuit, built-in 12A high-current MOS, efficiency up to 96%, module static power draw 25mA, optional 5V/9V/12V output. (Load normal recommendation <15W.
Output 5V: Current 3A;
Output 9V: Current 1.6A;
Output 12V: Current 1.2A )
UPS function: When the power supply is active, it powers the load directly through the boost circuit while also charging the lithium battery. If the power is interrupted, the battery path automatically activates to supply the load via the boost circuit. The 5V charging power source used by individual users employs an output capacitor with a larger capacitance value. This capacitor can continue to discharge after the power supply is turned off, causing the supply voltage to decline gradually, which may prevent the board from switching to battery power quickly after shutdown. If you encounter this situation, you can attach a discharge resistor of about 1K at the 5V input port